But he said he would not approach the remaining group games against Mexico and Cameroon with any caution as a result.

"I am not worried. I am going to play to win the second game," he said. "It [being on a yellow card] is not what I wanted, but that's the way it is. If I start thinking about it, that'll make it worse."

A change in the rules, brought in for the 2010 World Cup, means cards picked up during the group stage are no longer eradicated once that stage has been completed.

Instead they are accumulated until the quarterfinals, meaning two cautions in the first five matches can result in players missing key knockout games.

Brazil fear another booking for Neymar would mean he sits out the last-16 match -- which could be against defending champions Spain -- as a result.

But teammate Oscar said: "He is the guy that usually forces other people to get a yellow -- it's difficult to see him getting another.

"We are going to do all we can to let Neymar play without worrying about this, because we know that he is a player who can decide the game."